The newly-discovered supermassive black hole sits in the center of a ‘little red dot’ galaxy called CAPERS-LRD-z9 and is seen just 500 million years after the Big Bang.
An artist’s impression of CAPERS-LRD-z9. Image credit: Erik Zumalt, University of Texas at Austin.
“When looking for black holes, this is about as far back as you can practically go,” said Dr. Anthony Taylor, a postdoctoral researcher at the University of Texas at Austin.
“We’re really pushing the boundaries of what current technology can detect.”
“While astronomers have found a few, more distant candidates, they have yet to find the distinct spectroscopic signature associated with a black hole,” said Dr. Steven Finkelstein, also from the University of Texas at Austin.
In their research, the astronomers analyzed data collected by the NASA/ESA/CSA James Webb Space Telescope as part of the CAPERS (CANDELS-Area Prism Epoch of Reionization Survey) program.
Initially seen as an interesting speck in the program’s imagery, CAPERS-LRD-z9 turned out to be part of a new class of galaxies known as little red dots.
“The discovery of little red dots was a major surprise from early Webb data, as they looked nothing like galaxies seen with the NASA/ESA Hubble Space Telescope,” Dr. Finkelstein said,
“Now, we’re in the process of figuring out what they’re like and how they came to be.”
CAPERS-LRD-z9 adds to mounting evidence that supermassive black holes are the source of the unexpected brightness in little red dots.
Usually, that brightness would indicate an abundance of stars in a galaxy. However, little red dots exist at a time when such a large mass of stars is unlikely.
The galaxy may also help answer what causes the distinct red color in little red dots. That may be thanks to a thick cloud of gas surrounding the black hole, skewing its light into redder wavelengths as it passes through.
“We’ve seen these clouds in other galaxies,” Dr. Taylor said.
“When we compared this object to those other sources, it was a dead ringer.”
CAPERS-LRD-z9 is also notable for how colossal its black hole is.
Estimated as up to 300 million solar masses, its mass measures up to half that of all the stars in its galaxy. Even among supermassive black holes, this is particularly big.
Finding such a massive black hole so early on provides astronomers a valuable opportunity to study how these objects developed.
A black hole present in the later Universe will have had diverse opportunities to bulk up during its lifetime. But one present in the first few hundred million years wouldn’t.
“This adds to growing evidence that early black holes grew much faster than we thought possible,” Dr. Finkelstein said.
“Or they started out far more massive than our models predict.”
The discovery is reported in a paper in the Astrophysical Journal.
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Anthony J. Taylor et al. 2025. CAPERS-LRD-z9: A Gas-enshrouded Little Red Dot Hosting a Broad-line Active Galactic Nucleus at z = 9.288. ApJL 989, L7; doi: 10.3847/2041-8213/ade789
